The invention relates to an image processing method and apparatus.
Referring to FIG. 1, a typical computer system 5 may include a digital camera 12 that electrically captures an optical image 13 and a computer 10 that may store, print or display the captured image. To capture the image, the camera 12 typically includes an image sensor 11 that captures digitized portions of the image (called pixels) and communicates indications (digital bits, for example) of these pixels to the computer 10 (via a serial bus 14, for example).
The image sensor 11 typically does not respond to light frequencies in the same manner as the human eye. As a result, raw data that is provided by the image sensor 11 may need to be transformed so that the transformed data indicates the optical image 13 as perceived by the human eye. However, before this transformation occurs, the raw data may need to be manipulated to compensate for other effects introduced by the camera 12, such as stray lighting effects, lens flare effects and the nonlinearity of the image sensor 11. Also, the raw data may be manipulated to adjust a white color balance in the image that is indicated by the data.
The term “white color balance” refers to a measure of the balance of colors in the captured image. For example, when an image is captured under a florescent light, the raw data from the image sensor 11 may indicate a generally green image. To correct an incorrect white color balance, the computer 10 may scale the pixel intensities (that are indicated by the raw data from the image sensor 11). For example, the computer 10 may scale the pixel intensities that indicate red, green and blue color components of the optical image 13 by different factors (called αR, αG, and αB, respectively) to compensate for an white color imbalance.
Unfortunately, an image processing circuit, such as the above-described camera 12, may be specifically designed for a given image sensor and other components of the camera 12. Thus, there is a continuing need for an imaging processing circuit that more readily accommodates different camera components, such as image sensors that have different sizes and types, for example.